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NMR study of the exchange coupling in the trinuclear cluster of the multicopper oxidase Fet3p.

ABSTRACT: Fet3p from Saccharomyces cerevisiae is a multicopper oxidase (MCO) which oxidizes Fe(2+) to Fe(3+). The electronic structure of the different copper centers in this family of enzymes has been extensively studied and discussed for years with a particular focus on the exchange coupling regime in the trinuclear cluster (TNC). Using NMR spectroscopy we have quantified the exchange coupling constant in the type 3 center in a fully metalated oxidase; this value in Fet3p is significantly higher than that reported for proteins containing isolated type 3 centers as tyrosinase. We also provide evidence of exchange coupling between the type 2 and the type 3 Cu(2+) ions, which supports the crystallographic evidence of dioxygen binding to the TNC. This work provides the foundation for the application of NMR to these complex systems.

SUBMITTER: Zaballa ME

PROVIDER: S-EPMC2933071 | biostudies-literature | 2010 Aug

REPOSITORIES: biostudies-literature

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NMR study of the exchange coupling in the trinuclear cluster of the multicopper oxidase Fet3p.

Zaballa María-Eugenia ME Ziegler Lynn L Kosman Daniel J DJ Vila Alejandro J AJ

Journal of the American Chemical Society 20100801 32

Fet3p from Saccharomyces cerevisiae is a multicopper oxidase (MCO) which oxidizes Fe(2+) to Fe(3+). The electronic structure of the different copper centers in this family of enzymes has been extensively studied and discussed for years with a particular focus on the exchange coupling regime in the trinuclear cluster (TNC). Using NMR spectroscopy we have quantified the exchange coupling constant in the type 3 center in a fully metalated oxidase; this value in Fet3p is significantly higher than th ...[more]

PMID: 20698686

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Systematic perturbation of the trinuclear copper cluster in the multicopper oxidases: the role of active site asymmetry in its reduction of O2 to H2O.

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